Vehicular transmission device

ABSTRACT

A transmission device of a vehicle that can use a manual transmission. The transmission is provided with shift blocks for regulating shifting between gear positions so as to achieve automatic gear shifting. This vehicle transmission device includes the shift block for a reverse-1st speed, a 4th speed-5th speed, a 2nd speed-3rd speed, and a 6th speed arranged in this order in a selection operation direction. The vehicle transmission device also includes first through fourth shift levers that engage respectively with the shift blocks, a first select actuator that moves the first or second shift lever for a select operation, a first shift actuator that moves the first or second shift lever for a shift operation, a second select actuator that moves the third or fourth shift lever for the select operation, and a second shift actuator that moves the third or fourth shift lever for the shift operation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National Stage Application, which claims the benefit under 35 U.S.C. §371 of PCT International Patent Application No. PCT/JP2013/063684, filed May 16, 2013, which claims the foreign priority benefit under 35 U.S.C. §119 of Japanese Patent Application No. 2012-114753, filed May 18, 2012, the contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a transmission device of a vehicle in which gear shifting operations are automatized based on a manual transmission.

BACKGROUND ART

A general 6-speed manual transmission (hereinafter referred to as a transmission) will be described with reference to FIG. 8.

A transmission TM includes an input shaft 10, an output shaft 11, and a counter shaft 12. The output shaft 11 is disposed coaxially with this input shaft 10. The counter shaft 12 is disposed parallel to the input shaft 10 and output shaft 11. An input main gear 13 is disposed on the input shaft 10. A 1st speed (1st) main gear M1, a 2nd speed (2nd) main gear M2, a 3rd speed (3rd) main gear M3, a 4th speed (4th) main gear M4, and a reverse main gear MR are journally supported on the output shaft 11, and a 6th speed (6th) main gear M6 is fixedly secured on the output shaft 11. On the counter shaft 12, an input counter gear 14, a 1st speed counter gear C1, a 2nd speed counter gear C2, a 3rd speed counter gear C3, a 4th speed counter gear C4, and a reverse counter gear CR are fixedly secured, and a 6th speed counter gear C6 is journally supported. The input counter gear 14 engages with the input main gear 13. The 1st speed counter gear C1 engages with the 1st speed main gear M1. The 2nd speed counter gear C2 engages with the 2nd speed main gear M2. The 3rd speed counter gear C3 engages with the 3rd speed main gear M3. The 4th speed counter gear C4 engages with the 4th speed main gear M4. The reverse counter gear CR engages with the reverse main gear MR via an idle gear IR. The 6th speed counter gear C6 engages with the 6th speed main gear M6.

In this transmission TM, a sleeve S1 is spline-engaged with a hub H1 secured to the output shaft 11. When the sleeve S1 is spline-engaged with a dog DR of the reverse main gear MR, the output shaft 11 rotates reversely. When the sleeve S1 is spline-engaged with a dog D1 of the 1st speed main gear M1, the output shaft 11 rotates at a speed corresponding to the 1st speed. A sleeve S2 is spline-engaged with a hub H2 secured to the output shaft 11. When the sleeve S2 is spline-engaged with a dog D2 of the 2nd speed main gear M2, the output shaft 11 rotates at a speed corresponding to the 2nd speed. When the sleeve S2 is spline-engaged with a dog D3 of the 3rd speed main gear M3, the output shaft 11 rotates at a speed corresponding to the 3rd speed.

A sleeve S4 is spline-engaged with a hub H4 secured to the output shaft 11. When the sleeve S4 is spline-engaged with a dog D4 of the 4th speed main gear M4, the output shaft 11 rotates at a speed corresponding to the 4th speed. When the sleeve S4 is spline-engaged with a dog D5 of the input main gear 13, the output shaft 11 rotates at a speed corresponding to the 5th speed (5th) (in the directly-coupled state). A sleeve S6 is spline-engaged with a hub H6 secured to the counter shaft 12. When the sleeve S6 is spline-engaged with a dog D6 of the 6th speed counter gear C6, the output shaft 11 rotates at a speed corresponding to the 6th speed.

The sleeves S1, S2, S4, and S6 are manually operated by a driver with a driver's shift lever within the driver's cabin via shift forks F1, F2, F4, and F6 and a shift shaft.

A shift control system in an actual transmission will be described with reference to FIG. 9 and FIG. 10.

In FIG. 9 and FIG. 10, a low speed shift shaft 15 a and a high speed shift shaft 15 b are disposed parallel to the vehicle width direction and along the longitudinal direction of the vehicle. At a rear portion of the low speed shift shaft 15 a, a first shift fork F1 is fixedly secured. The first shift fork F1 shifts between the 1st speed and the reverse (Rev). In front of the first shift fork F1, a second shift fork F2 is disposed to be movable with respect to the shift shaft 15 a. The second shift fork F2 shifts between the 2nd speed and the 3rd speed.

On the other hand, a third shift fork F4 is disposed at a front portion of the high speed shift shaft 15 b such that the third shift fork F4 is movable with respect to the shift shaft 15 b. The third shift fork F4 shifts between the 4th speed and the 5th speed. At the rear portion of the shift shaft 15 b, a counter shaft shift 15 c is disposed parallel to the shift shaft 15 b. The shift shaft 15 b and the counter shaft shift 15 c are coupled together by a link lever 16. On this counter shaft shift 15 c, a fourth shift fork F6 is fixedly secured. The fourth shift fork F6 shifts to the 6th speed.

On the low speed shift shaft 15 a, a boss 17 a is disposed in front of the second shift fork F2. A reverse-1st speed shift block B1 is integral with the boss 17 a. On the high speed shift shaft 15 b, a boss 17 b is disposed behind the third shift fork F4. A 6th speed shift block B6 is integral with the boss 17 b.

Between the reverse-1st speed shift block B1 and the 6th speed shift block B6, a 2nd speed-3rd speed shift block B2 and a 4th speed-5th speed shift block B4 are arranged. The 2nd speed-3rd speed shift block B2 is coupled to the second shift fork F2 by a coupling member 18 a. The 4th speed-5th speed shift block B4 is coupled to the third shift fork F4 by a coupling member 18 b.

The reverse-1st speed shift block B1, the 2nd speed-3rd speed shift block B2, the 4th speed-5th speed shift block B4, and the 6th speed shift block B6 are arranged from the low speed gear to the high speed gear. With the operation of the driver's shift lever, select operations are sequentially performed from the neutral position of the reverse-1st speed to those of the 2nd speed-3rd speed, the 4th speed-5th speed, and the 6th speed. Subsequently, a shift operation is performed from the neutral position of the selected shift block B1, B2, B4, or B6 to a desired gear position (shift position).

That is, when the shift lever engages with the 1st speed shift block B1, the reverse-1st speed shift block B1 is moved forward by the shift lever. Accordingly, the first shift fork F1 is moved forward via the boss 17 a and the shift shaft 15 a so as to shift from the neutral position to the 1st speed. When the 1st speed shift block B1 is moved rearward, the first shift fork F1 is moved rearward so as to shift from the neutral position to the reverse gear position.

When switching to the 2nd speed or the 3rd speed is desired, the engagement position of the shift lever is moved to the neutral position of the 2nd speed-3rd speed shift block B2 by the select operation. From this state, the 2nd speed-3rd speed shift block B2 is moved rearward by the shift lever. Accordingly, the second shift fork F2 is moved rearward via the coupling member 18 a so as to shift from the neutral position to the 2nd speed. The 2nd speed-3rd speed shift block B2 is moved forward so as to shift from the neutral position to the 3rd speed.

When switching to the 4th speed or the 5th speed is desired, the shift lever is moved to the neutral position of the 4th speed-5th speed shift block B4 by the select operation. Subsequently, the 4th speed-5th speed shift block B4 is moved rearward. Accordingly, the third shift fork F4 is moved rearward via the coupling member 18 b so as to shift from the neutral position to the 4th speed. The 4th speed-5th speed shift block B4 is moved forward so as to shift from the neutral position to the 5th speed.

When switching to the 6th speed is desired, the shift lever is moved to the neutral position of the 6th speed shift block B6 by the select operation. Subsequently, the 6th speed shift block B6 is moved rearward. Accordingly, the shift shaft 15 b is moved rearward via the boss 17 b, and the counter shaft shift 15 c is moved forward via the link lever 16. Thus, the fourth shift fork F6 is moved forward so as to shift from the neutral position to the 6th speed.

In FIG. 9 and FIG. 10, reference numeral 19 denotes ball clicks for holding the shafts 15 a and 15 b at the respective gear positions and neutral positions.

FIG. 11(a) illustrates the above-described shift patterns of the transmission TM.

In FIG. 11(a), the 1st speed shift block B1 described with reference to FIG. 9 and FIG. 10 is used to perform a shift operation between the reverse and the 1st speed (shift operation to the reverse or to the 1st speed). The 2nd speed-3rd speed shift block B2 is used to perform a shift operation between the 2nd speed and the 3rd speed (shift operation to the 2nd speed or to the 3rd speed). The 4th speed-5th speed shift block B4 is used to perform a shift operation between the 4th speed and the 5th speed (shift operation to the 4th speed or to the 5th speed). The 6th speed shift block B6 is used to perform a shift operation to the 6th speed. When the shift lever is moved by the select operation, the shift lever is moved along the aligned neutral positions of the reverse-1st speed shift block B1, the 2nd speed-3rd speed shift block B2, the 4th speed-5th speed shift block B4, and the 6th speed shift block B6.

A gear shifting operation with this manual transmission will be described. For example, in the case from the 2nd speed to the 3rd speed, as illustrated in FIG. 11(b), the gear is disengaged from the 2nd speed to the neutral position. Subsequently, the gear is engaged from the neutral position to the 3rd speed. This is straight shifting (i.e., shifting without the select operation). As illustrated in FIG. 11(c), in the case of a gear shift operation from the 3rd speed to the 4th speed, the gear is disengaged from the 3rd speed to the neutral position. Subsequently, a select operation is performed on the shift lever so as to move to the neutral position of the 4th speed-5th speed shift block B4, and the gear is engaged from the neutral position to the 4th speed. This is an elbow plus elbow (crank) shifting (i.e., shifting with the select operation).

Operations similar to the above-described operations are required in an automatic transmission that is equipped with an automatic shifting device prepared based on the transmission illustrated in FIG. 9 and FIG. 10.

That is, it is necessary to provide shift levers to be selectively engaged with the reverse-1st speed shift block B1, the 2nd speed-3rd speed shift block B2, the 4th speed-5th speed shift block B4, and the 6th speed shift block B6. The shift levers are driven by actuators such as motors to move the shift blocks B1, B2, B4, and B6.

In the case where the shift operation is performed with the actuators, the rotation speed of the engine and the rotation speed of the output shaft are detected by rotation sensors in the transmission TM described with reference to FIG. 8. The detection results are introduced to an engine control unit (ECU). Based on a gear shift map (speed change map) stored in the ECU, a drive control is performed on the actuator associated with the appropriate (desired) gear position to achieve the desired gear shifting.

LISTING OF REFERENCES

PATENT LITERATURE 1: Japanese Patent Application Laid-Open Publication (Kokai) No. 2003-240115

PATENT LITERATURE 2: Japanese Patent Application Laid-Open Publication No. 2010-159823

A general automatic shifting device, which has one actuator for the shift operation and one actuator for the select operation, requires the following operations for the elbow plus elbow shifting. Specifically, disengagement of the gear, a select operation, and a shift operation for engaging the gear are sequentially performed. Additionally, the ECU needs time to determine, by means of its hardware and software, that the respective operations are completed. Accordingly, there is a problem that the elbow plus elbow shifting requires more time for speed change (gear shifting) as compared with the straight shifting.

To cope with this problem, as illustrated in FIG. 12, actuators A1, A2, A4, and A6 are disposed. The actuators A1, A2, A4, and A6 independently operate the shift blocks B1, B2, B4, and B6. These actuators A1, A2, A4, and A6 are sequentially driven so as to eliminate the shift operation. The straight shifting is defined as an ordinary shift operation (the shift operation from the 2nd speed to the 3rd speed in the drawing). The elbow plus elbow shifting only needs to disengage the gear from the current gear position (the shift operation from the 3rd speed to the neutral position in the drawing), make a determination of the gear disengagement in the position enclosed by a circle illustrated in the drawing, and then perform the shift operation to the desired gear position (the shift operation in the shift block B4 from the neutral position to the 4th speed in the drawing) for gear engagement.

While this automatic shifting device of FIG. 12 can be fabricated based on the transmission illustrated in FIG. 8 to FIG. 10, the actuators A1, A2, A4, and A6 are required corresponding to the number of the shift blocks B1, B2, B4, and B6. When these actuators A1, A2, A4, and A6 should be mounted, it is not easy to find good locations for the mounting, and the driving circuit (mechanism) of these actuators is also required. For hydraulic or pneumatic actuators, the actuators can be made from cylinders and pistons, but there is a problem that hydraulic piping or pneumatic piping and a hydraulic source or a pneumatic source are required.

Alternatively, as illustrated in FIG. 13, odd speed gear positions are paired, and even gear positions are paired so as to enable straight shifting. Specifically, the straight shifting is enabled between the 1st speed and the 3rd speed, the straight shifting is enabled between the 5th speed and the reverse, the straight shifting is enabled between the 2nd speed and the 4th speed, and the straight shifting is enabled to the 6th speed. For the 1st speed-3rd speed and the 5th speed-reverse, the shift operation is performed with an odd-number-pair actuator Ao. For the 2nd speed-4th speed and the 6th speed, the shift operation is performed with an even-number-pair actuator Ae. Accordingly, in the shift operation from the 2nd speed to the 3rd speed, the gear position is shifted from 2nd speed to the neutral position by the even-number-pair actuator Ae, and the gear is disengaged. Subsequently, a determination on the gear disengagement is made. Then, the shift operation can be performed from the neutral position to the 3rd speed by the odd-number-pair actuator Ao, and the gear is engaged. From the 3rd speed to the 4th speed, the gear position is shifted from the 3rd speed to the neutral position by the odd-number-pair actuator Ao and the gear is disengaged. Subsequently, a determination on the gear disengagement is made. Then, the shift operation can be performed from the neutral position to 4th speed by the even-number-pair actuator Ae, and the gear is engaged.

The automatic shifting device of FIG. 13 can operate with the odd-number-pair actuator Ao, the even-number-pair actuator Ae, and the actuator for select operation. This allows reducing the number of actuators. Also, because this allows performing the select operation prior to shifting the gear position, the time for the gear shifting is not adversely influenced.

However, the arrangement of the shift forks in the shift control system of the transmission described with reference to FIG. 9 and FIG. 10 corresponds to the respective gear positions of the transmission described with reference to FIG. 8. Therefore, the shift pattern of FIG. 13 cannot be applied to an existing manual transmission, and requires a dedicated transmission. This becomes a factor that significantly worsens the cost.

Therefore, as illustrated in FIG. 14, the arrangement of the shift blocks B1, B2, B4, and B6 is unchanged, and the shift operations of the shift block B1 in the first row and the shift block B4 in the third row are performed by an actuator Aa whereas the shift operations of the shift block B2 in the second row and the shift block B6 in the fourth row are performed by an actuator Ab. This shift pattern can be applied to the existing manual transmission.

However, when the shift operations of the shift block B1 in the first row and the shift block B4 in the third row are performed by the actuator Aa and the shift operations of the shift block B2 in the second row and the shift block B6 in the fourth row are performed by the actuator Ab, it is necessary to arrange the actuators Aa and Ab opposed to each other across the shift blocks B1, B2, B4, and B6. Additionally, there is a problem that the mechanism for the select operation becomes complicated. This causes an increase in size, complication, and deterioration in cost of the automatic shifting device.

SUMMARY OF THE INVENTION

Therefore, an object of the present invention to provide a transmission device (speed change apparatus) of a vehicle that can solve the above-described problems and perform an automatic gear shift using a manual transmission without modifications.

To achieve the above-described object, the present invention provides a transmission device of a vehicle using a transmission. In the transmission, gear positions of a reverse and a 1st speed can be arranged opposite to one another, gear positions of a 2nd speed and a 3rd speed can be arranged opposite to one another, gear positions of a 4th speed and a 5th speed can be arranged opposite to one another, and a gear position of a 6th speed can be disposed. The transmission device includes shift blocks used for shift operations to the gear positions. The transmission is configured to perform select operations and then perform shift operations of the shift blocks for automatic gear shifting. The transmission device of the vehicle includes first to fourth shift levers, a first select actuator, a first shift actuator, a second select actuator, and a second shift actuator. The shift blocks are arranged in the order from the shift block of the reverse-1st speed, the shift block of the 4th speed-5th speed, the shift block of the 2nd speed-3rd speed, and the shift block of the 6th speed in a direction of the select operation. The first to fourth shift levers engage with the shift blocks. The first select actuator is configured to move, by the select operation, the first or second shift lever engaged with the shift block of the reverse-1st speed or the shift block of the 4th speed-5th speed. The first shift actuator is configured to move the first or second shift lever by the shift operation. The second select actuator is configured to move, by the select operation, the third or fourth shift lever engaged with the shift block of the 2nd speed-3rd speed or the shift block of the 6th speed. The second shift actuator is configured to perform a shift operation of the third or fourth shift lever that has moved by the select operation of the second select actuator.

In this transmission device, the gear positions of the reverse and the 1st speed can be arranged opposite to one another, the gear positions of the 2nd speed and the 3rd speed can be arranged opposite to one another, the gear positions of the 4th speed and the 5th speed can be arranged opposite to one another, and shift shafts parallel to one another can be disposed at the gear position of the 6th speed. A first shift fork is fixedly secured to one of the shift shafts (first shift shaft), and the shift block of the reverse-1st speed is also fixedly secured to the same shift shaft (first shift shaft). The first shift fork is configured to shift the gear positions of the reverse and the 1st speed. A second shift fork is disposed on the same shift shaft (first shift shaft) such that the second shift fork is movable in an axial direction. The second shift fork is configured to shift the gear positions of the 2nd speed and the 3rd speed. The shift block of the 2nd speed-3rd speed is coupled to the second shift fork. A fourth shift fork is coupled to the other shift shaft (second shift shaft) via a link lever, and the shift block of the 6th speed is fixedly secured to the second shift shaft. The fourth shift fork is configured to shift to the gear position of the 6th speed. A third shift fork is disposed on the second shift shaft such that the third shift fork is movable in an axial direction. The third shift fork is configured to shift the gear positions of the 4th speed and the 5th speed. The shift block of the 4th speed-5th speed is coupled to the third shift fork.

In this transmission device, each of the first shift lever and the second shift lever can be formed in an L shape. The first shift lever is spaced from the second shift lever in an up-down direction, and the first and second shift levers are disposed to be turnable horizontally. Each of the first shift lever and the second shift lever has a lever portion in the L-folded part. The lever portion of the first shift lever engages with the shift block of the reverse-1st speed, and the lever portion of the second shift lever engages with the shift block of the 4th speed-5th speed. Turning of the first shift lever and the second shift lever causes moving, by the shift operation, of the shift block of the reverse-1st speed and the shift block of the 4th speed-5th speed via the lever portions.

In this transmission device, each of the third shift lever and the fourth shift lever can be formed in an L shape. The third shift lever is spaced from the fourth shift lever in the up-down direction, and the third and fourth shift levers are disposed to be turnable horizontally. The third shift lever and the fourth shift lever are disposed opposite the first shift lever and the second shift lever. Each of the third shift lever and the fourth shift lever has a lever portion in the L-folded part. The lever portion of the third shift lever engages with the shift block of the 2nd speed-3rd speed, and the lever portion of the fourth shift lever engages with the shift block of the 6th speed-5th speed. Turning of the third shift lever and the fourth shift lever causes moving, by the shift operation, of the shift block of the 2nd speed-3rd speed and the shift block of the 6th speed via the lever portions.

In this transmission device, each of the first and second select actuators can include a select motor and a shift cylindrical body. The shift cylindrical body engages with any of rear ends of the first and second shift levers or the third and fourth shift levers upon rotation of the select motor. Each of the first and second shift actuators includes a shift motor and a ball screw for reciprocating the shift cylindrical body in a shift operation direction. The ball screw is coupled to the shift motor and threadably mounted on the shift cylindrical body.

With the present invention, simply changing the arrangement order of the shift blocks provides an excellent effect that allows automatic gear shifting with a simple structure using the existing manual transmission.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view illustrating a shift control system and an automatic shifting device of a transmission device of a vehicle according to one embodiment of the present invention.

FIG. 2 is a perspective view illustrating the shift control system of the transmission device of the vehicle according to the embodiment of the present invention.

FIG. 3 is a plan view of FIG. 2.

FIG. 4 is a perspective view illustrating the automatic shifting device of the transmission device of the vehicle according to the embodiment of the present invention.

FIG. 5 is a front view of FIG. 4.

FIG. 6 illustrates the detail of a shifting unit and an actuator in FIG. 4.

FIGS. 7(a) and 7(b) are diagrams illustrating shift patterns and gear shifting operations in the transmission device of the vehicle according to the embodiment of the present invention.

FIG. 8 is a skeleton diagram of an existing transmission to be used in the embodiment of the present invention.

FIG. 9 is a perspective view illustrating a shift control system of a conventional transmission device of a vehicle.

FIG. 10 is a plan view of FIG. 9.

FIGS. 11(a)-11(c) are diagrams illustrating shift patterns and gear shifting operations in the conventional transmission device of the vehicle.

FIG. 12 is a diagram illustrating shift patterns and gear shifting operations when the automatic shifting device is applied to the conventional transmission device of the vehicle.

FIG. 13 is a diagram illustrating other shift patterns and gear shifting operations of the automatic shifting device.

FIG. 14 is a diagram illustrating other shift patterns and gear shifting operations when the automatic shifting device is applied to the conventional transmission.

DETAILED DESCRIPTION

The following describes embodiments of the present invention in detail with reference to the accompanying drawings.

The transmission TM to be used in the embodiment of the present invention is as described in FIG. 8. Thus, the description of the transmission TM is omitted.

Next, a description will be given of a shift control system of the transmission TM of FIG. 8 with reference to FIG. 1 to FIG. 3.

This shift control system of the transmission TM in FIG. 1 to FIG. 3 is basically the same as the conventional shift control system described with reference to FIG. 9 and FIG. 10. Same or like reference numerals designate identical or corresponding elements in the following description.

In the shift control system of FIG. 1 to FIG. 3, the arrangement configuration of the shift shafts 15 a and 15 b and the first to fourth shift forks F1, F2, F4, and F6 are the same. This configuration will be described below. The low speed and high speed shift shafts 15 a and 15 b are disposed parallel to the vehicle width direction and along the longitudinal direction of the vehicle direction. At the rear portion of the low speed shift shaft 15 a, the first shift fork F1 is fixedly secured. The first shift fork F1 shifts between the 1st speed and the reverse (Rev). In front of the first shift fork F1, the second shift fork F2 is disposed to be movable in the axial direction with respect to the shift shaft 15 a. The second shift fork F2 shifts between the 2nd speed and the 3rd speed.

On the other hand, the third shift fork F4 is disposed at the front portion of the high speed shift shaft 15 b such that the third shift fork F4 is movable in the axial direction with respect to the shift shaft 15 b. The third shift fork F4 shifts between the 4th speed and the 5th speed. At (near) the rear portion of the shift shaft 15 b, the counter shaft shift 15 c is disposed parallel to the shift shaft 15 b. The shift shaft 15 b and the counter shaft shift 15 c are coupled together by the link lever 16. The fourth shift fork F6 is fixedly secured on the counter shaft shift 15 c. The fourth shift fork F6 shifts to the 6th speed.

For the shift shafts 15 a and 15 b, the second shift fork F2, and the third shift fork F4, the respective gear positions and neutral positions are held by the ball clicks 19.

The difference between the shift control system in FIG. 1 to FIG. 3 and the shift control system in FIG. 9 and FIG. 10 lies in that the arrangement order of the shift blocks B1, B2, B4, and B6 is changed.

Specifically, the shift block B1 of the reverse-1st speed, the shift block B4 of the 4th speed-5th speed, the shift block B2 of the 2nd speed-3rd speed, and the shift block B6 of the 6th speed are arranged in the select operation direction from the low speed shift shaft 15 a to the high speed shift shaft 15 b in FIGS. 9 and 10. When this arrangement is compared with the arrangement illustrated in FIGS. 9 and 10, the shift block B2 of the 2nd speed-3rd speed and the shift block B4 of the 4th speed-5th speed are reversed in position.

The shift block B1 of the reverse-1st speed is fixedly secured on the shift shaft 15 a via the boss 17 a. The shift block B6 of the 6th speed is fixedly secured on the other shift shaft 15 b via the boss 17 b. The shift block B4 of the 4th speed-5th speed is coupled to the third shift fork F4 by a coupling member 21 a. The shift block B2 of the 2nd speed-3rd speed is coupled to the second shift fork F2 by a coupling member 21 b.

In the shift block B2 of the 2nd speed-3rd speed, an elongated hole 22 is formed. As illustrated in FIG. 5, a guide shaft 23 is inserted into the elongated hole 22. The guide shaft 23 is disposed at the boss 17 b of the shift block B6 of the 6th speed. The elongated hole 22 of the shift block B2 and the guide shaft 23 guide the movement of the shift block B6 of the 6th speed in the shift operation direction. It should be noted that an elongated hole 22 is also formed in the shift block B4 of the 4th speed-5th speed because the shift block B4 having the elongated hole 22 can be fabricated as a common component with the shift block B2 of the 2nd speed-3rd speed.

With the shift blocks B1, B4, B2, and B6 arranged in this manner, first to fourth shift levers 24 a, 25 a, 25 b, 24 b are respectively engaged in the arrangement order. The shift operations are performed with the first to fourth shift levers 24 a, 25 a, 25 b, and 24 b.

As illustrated in FIG. 1, FIG. 4, and FIG. 5, the first shift lever 24 a and the second shift lever 25 a are disposed opposite to the third shift lever 25 b and the fourth shift lever 24 b, and are formed in an L shape.

As illustrated in FIG. 5, the second shift lever 25 a and the first shift lever 24 a are disposed to be distant from each other in the up-down direction (height direction) and to be turnable horizontally (in a horizontal plane) about a shaft 28 a. In the first shift lever 24 a, a lever portion 26 a in the L folded part engages with the shift block B1 of the reverse-1st speed. In the second shift lever 25 a, a lever portion 27 a in the L folded part engages with the shift block B4 of the 4th speed-5th speed.

The third shift lever 25 b and the fourth shift lever 24 b are disposed to be distant from each other in the up-down direction and to be turnable in the horizontal plane about to a shaft 28 b. In the third shift lever 25 b, a lever portion 27 b in the L folded part engages with the shift block B2 of the 2nd speed-3rd speed. In the fourth shift lever 24 b, a lever portion 26 b in the L folded part engages with the shift block B6 of the 6th speed.

The first to fourth shift levers 24 a, 25 a, 25 b, and 24 b are turned around the shafts 28 a and 28 b so as to move, by the shift operation, the respective shift blocks B1, B4, B2, and B6 via the associated lever portions 26 a, 27 a, 27 b, and 26 b.

The first shift lever 24 a, which shifts the shift block B1 of the reverse-1st speed, or the second shift lever 25 a, which shifts the shift block B4 of the 4th speed-5th speed, is moved by a first select actuator 30 a for the select operation. After the select operation, the first shift lever 24 a or the second shift lever 25 a is moved by a first shift actuator 31 a for the shift operation.

The third shift lever 25 b, which shifts the shift block B2 of the 2nd speed-3rd speed, or the fourth shift lever 24 b, which shifts the shift block B6 of the 6th speed, is moved by a second select actuator 30 b for the select operation. After the select operation, the third shift lever 25 b or the fourth shift lever 24 b is moved by a second shift actuator 31 b for the shift operation.

The first and second select actuators 30 a and 30 b include select motors 33 a and 33 b and rotatable shift cylindrical bodies 34 a and 34 b. The shift cylindrical body 34 a or 34 b engages with any of the rear ends of the first and second shift levers 24 a and 25 a or the rear ends of the third and fourth shift levers 25 b and 24 b (the rear ends opposite the lever portions 26 a, 27 a, 27 b, and 26 b) upon rotation of the select motor 33 a or 33 b. Turning gears 35 a and 35 b are disposed at the select motors 33 a and 33 b. At the shift cylindrical bodies 34 a and 34 b, select gears 36 a and 36 b are disposed. The select gears 36 a and 36 b engage with the turning gears 35 a and 35 b. On the opposite sides of the select gears 36 a and 36 b at the shift cylindrical bodies 34 a and 34 b, a pair of engagement protrusions 37 a and 37 b are disposed. The engagement protrusion 37 a or 37 b engages with any of the rear ends of the first and second shift levers 24 a and 25 a or the rear ends of the third and fourth shift levers 25 b and 24 b (the rear ends opposite the lever portions 26 a, 27 a, 27 b, and 26 b).

The first and second shift actuators 31 a and 31 b include shift motors 40 a and 40 b and ball screws 41 a and 41 b (FIG. 6). The ball screws 41 a and 41 b are coupled to the shift motors 40 a and 40 b, and are threadably mounted on nut portions 38 a and 38 b of the shift cylindrical bodies 34 a and 34 b so as to reciprocate the shift cylindrical bodies 34 a and 34 b in the shift operation direction.

U-shaped interlock plates 42 a and 42 b are disposed on the shafts of the ball screws 41 a and 41 b. The interlock plates 42 a and 42 b house (receive) the distal end portions of the engagement protrusions 37 a and 37 b of the shift cylindrical bodies 34 a and 34 b, and the rotations of the interlock plates 42 a and 42 b are restricted (regulated) by the shift cylindrical bodies 34 a and 34 b. The interlock plates 42 a and 42 b have interlock grooves 43 a and 43 b and depression grooves (recesses) 44 a and 44 b. The interlock grooves 43 a and 43 b guide the shift cylindrical bodies 34 a and 34 b in the shift operation direction. The grooves 44 a and 44 b receive the rear ends of the first to fourth shift levers 24 a, 25 a, 25 b, and 24 b between the engagement protrusions 37 a and 37 b. Movements of the shift levers 24 a, 25 a, 25 b, and 24 b that are not selected by the engagement protrusions 37 a and 37 b are restricted (regulated) by the grooves 44 a and 44 b.

The first and second select actuators 30 a and 30 b control the rotation positions of the shift cylindrical bodies 34 a and 34 b via the turning gears 35 a and 35 b and the select gears 36 a and 36 b with the forward direction rotation or the reverse direction rotation of the select motors 33 a and 33 b. The first and second select actuators 30 a and 30 b select one of the two positions of the engagement protrusions 37 a and 37 b. At one of the two positions (higher position), the engagement protrusions 37 a and 37 b are engaged with the rear ends of the second shift lever 25 a and the third shift lever 25 b (the rear ends opposite the lever portions 27 a and 27 b). At the other position (lower position), the engagement protrusions 37 a and 37 b are engaged with the rear ends of the first and fourth shift levers 24 a and 24 b (the rear ends opposite the lever portions 26 a and 26 b).

In the state where the second shift lever 25 a and the third shift lever 25 b in the upper position are selected or the second shift lever 24 a and the fourth shift lever 24 b in the lower position are selected, the shift motors 40 a and 40 b of the first and second shift actuators 31 a and 31 b are rotated in the forward rotation direction or the reverse rotation direction. Upon the rotations of the shift motors, the shift cylindrical bodies 34 a and 34 b are moved from the neutral position in the shift operation direction by the ball screws 41 a and 41 b. Accordingly, the first to fourth shift levers 24 a, 25 a, 25 b, and 24 b are turned around the shafts 28 a and 28 b so as to move the shift blocks B1, B4, B2, and B6 in the shift operation direction via the lever portions 26 a, 27 a, 27 b, and 26 b. Thus, the gear is engaged at a desired gear position or the gear is disengaged from a desired gear position to the neutral position.

A description will be given of an automatic shift operation in the above-described automatic shifting device using FIGS. 7(a) and 7(b).

Firstly, as described above, when selecting (deciding) a particular gear position, the ECU selects the gear position using the engine rotation speed, the engine load, the output shaft rotation speed (vehicle speed), and other parameters based on a speed change map that is stored in the ECU beforehand.

At the time of the straight shifting for shifting the gear position from the 2nd speed to the 3rd speed in FIG. 7(a), the second select actuator 30 b illustrated in FIG. 1, FIG. 4, and FIG. 5 moves the shift cylindrical body 34 b for the shift operation when the second shift actuator 31 b is driven, with the engagement protrusion 37 b being engaged with the third shift lever 25 b (with the engagement protrusion 37 b being held in this rotation position). As the third shift lever 25 b is turned, with the lever portion 27 b of the third shift lever 25 b being engaged with the shift block B2, the shift block B2 is moved from the 2nd speed position to the 3rd speed position so as to shift the gear position from the 2nd speed to the 3rd speed.

At the time of shifting from the 3rd speed to the 4th speed, the second shift actuator 31 b moves the shift block B2 from the 3rd speed position to a neutral position N. Then, the ECU confirms the gear disengagement from the 3rd speed. Subsequently, the first shift actuator 31 a turns the second shift lever 25 a so as to move the shift block B4 from the neutral position N to the 4th speed position. Thus, the gear position is shifted to the 4th speed.

When this shift block B2 is moved up to the neutral position N, the ECU performs a select operation such that the first select actuator 30 a moves the shift block B4 using the second shift lever 25 a for the select operation. After the shift block B2 is moved up to the neutral position N and the gear is disengaged, the first shift actuator 31 a can immediately move the shift block B2 to the 4th speed position. This eliminates a need for the elbow plus elbow shifting described in the conventional arrangement.

Thus, the two independent first and second shift actuators 31 a and 31 b are used for the shift operation. Accordingly, when the shift block B2 of the 2nd speed-3rd speed in FIG. 7(a) is in the 2nd speed or the 3rd speed, the first select actuator 30 a can move the shift block B4 for the select operation in advance. At the time of shifting from the 3rd speed to the 4th speed, it is possible to confirm that the gear is in the neutral position (i.e., gear disengagement is made) illustrated by a circle, and then shift to the 4th speed. At the time of shifting from the 4th speed to the 5th speed, it is only necessary to directly perform straight shifting of the shift block B4. Furthermore, at the time of shifting from the 5th speed to the 6th speed, it is only necessary to return the shift block B4 from the 5th speed to the neutral position N using the first shift actuator 31 a and to move the shift block B6 from the neutral position N to the 6th speed using the second shift actuator 31 b.

In FIG. 7(a), it is only necessary to directly perform straight shifting for the change in gear position from the 5th speed to the 4th speed and from the 3rd speed to the 2nd speed. When changing the gear position from the 4th speed to the 3rd speed, the second select actuator 30 b can move the shift block B2 for the select operation in advance. When changing the gear position from the 2nd speed to the 1st speed, the first select actuator 30 a can move the shift block B1 for the select operation. Thus, these changes are substantially performed by straight shifting.

In the case where the current gear position is in the 1st speed as illustrated in FIG. 7(b), one of shifting from the 1st speed to the reverse (Rev) and shifting from the 1st speed to the 2nd speed is performed. When shifting from the 1st speed to the reverse, it is only necessary to directly perform straight shifting using the first shift actuator 31 a. When shifting from the 1st speed to the 2nd speed, the second select actuator 30 b can perform a select operation of the shift block B2 in advance. Thus, it is only necessary to move the gear position from the 1st speed to the neutral position N, confirm the gear disengagement, and then perform a shift operation of the shift block B2 from the neutral position N to the 3rd speed position.

As described above, the embodiment of the present invention uses the conventional transmission. The shift block B2 of the 2nd speed-3rd speed and the shift block B4 of the 4th speed-5th speed are reversed in position, as compared with the conventional shift block arrangement. In the conventional shift block arrangement, the shift blocks are arranged in the order from the low speed gear to the high speed gear. In the embodiment of the present invention, the shift blocks B2 and B4 are coupled to the shift forks F2 and F4 via the coupling members 21 a and 21 b. This simple configuration allows an automatic shift with a simple structure using the existing manual transmission, and eliminates the unnecessary select operation in the elbow plus elbow shifting.

EXPLANATION OF REFERENCE NUMERALS

-   -   24 a first shift lever     -   25 a second shift lever     -   25 b third shift lever     -   24 b fourth shift lever     -   30 a first select actuator     -   30 b second select actuator     -   31 a first shift actuator     -   31 b second shift actuator     -   B1, B4, B2, B6 shift block 

What is claimed is:
 1. A transmission device of a vehicle using a transmission, the transmission having a reverse gear position and a 1st speed gear position arranged opposite to one another, a 2nd speed gear position and a 3rd speed gear position arranged opposite to one another, a 4th speed gear position and a 5th speed gear position arranged opposite to one another, and a 6th speed gear position, with shift blocks configured to shift into the gear positions by a shift operation, the transmission being configured to perform a select operation and then perform the shift operation of the shift blocks for an automatic gear shifting, the transmission device comprising: the shift blocks including a shift block of a reverse-1st speed, the shift block of a 4th speed-5th speed, a shift block of a 2nd speed-3rd speed, and a shift block of a 6th speed arranged in a direction of the select operation; first to fourth shift levers configured to engage with the shift blocks, a first select actuator configured to move, by the select operation, the first shift lever engaged with the shift block of the reverse-1st speed or the second shift lever engaged with the shift block of the 4th speed-5th speed; a first shift actuator configured to move the first or second shift lever by the shift operation; a second select actuator configured to move, by the select operation, the third shift lever engaged with the shift block of the 2nd speed-3rd speed or the fourth shift lever engaged with the shift block of the 6th speed; and a second shift actuator configured to perform the shift operation of the third or fourth shift lever that has moved by the select operation of the second select actuator.
 2. The transmission device of the vehicle according to claim 1, wherein the gear positions of the reverse and the 1st-speed are arranged opposite to one another, the gear positions of the 2nd speed and the 3rd speed are arranged opposite to one another, the gear positions of the 4th speed and the 5th speed are arranged opposite to one another, first and second shift shafts parallel to one another are disposed at the gear position of the 6th speed, a first shift fork is fixedly secured to the first shift shaft, the shift block of the reverse-1st speed is fixedly secured to the first shift shaft, the first shift fork is configured to shift the gear positions of the reverse and the 1st speed, a second shift fork is disposed on the first shift shaft such that the second shift fork is movable in an axial direction, the second shift fork is configured to shift the gear positions of the 2nd speed and the 3rd speed, the shift block of the 2nd speed-3rd speed is coupled to the second shift fork, a fourth shift fork is coupled to the second shift shaft via a link lever, the shift block of the 6th speed is fixedly secured to the second shift shaft, the fourth shift fork is configured to shift to the gear position of the 6th speed, a third shift fork is disposed on the second shift shaft such that the third shift fork is movable in the axial direction, the third shift fork is configured to shift the gear positions of the 4th speed and the 5th speed, and the shift block of the 4th speed-5th speed is coupled to the third shift fork.
 3. The transmission device according to claim 1, wherein each of the first shift lever and the second shift lever is formed in an L shape, the first shift lever is spaced from the second shift lever in an up-down direction, the first and second shift levers are turnable horizontally, each of the first shift lever and the second shift lever has a lever portion in an L-folded part, the lever portion of the first shift lever engages with the shift block of the reverse-1st speed, the lever portion of the second shift lever engages with the shift block of the 4th speed-5th speed, and turning of the first shift lever and the second shift lever causes moving, by the shift operation, of the shift block of the reverse-1st speed and the shift block of the 4th speed-5th speed via the lever portions.
 4. The transmission device of the vehicle according to claim 3, wherein each of the third shift lever and the fourth shift lever is formed in an L shape, the third shift lever is spaced from the fourth shift lever in an up-down direction, the third and fourth shift levers are turnable horizontally, the third shift lever and the fourth shift lever are disposed opposite the first shift lever and the second shift lever, each of the third shift lever and the fourth shift lever has a lever portion in an L-folded part, the lever portion of the third shift lever engages with the shift block of the 2nd speed-3rd speed, the lever portion of the fourth shift lever engages with the shift block of the 6th speed, and turning of the third shift lever and the fourth shift lever causes moving, by the shift operation, of the shift block of the 2nd speed-3rd speed and the shift block of the 6th speed via the lever portions.
 5. The transmission device of the vehicle according to claim 1, wherein each of the first and second select actuators includes a select motor and a shift cylindrical body, the shift cylindrical body engages with any of rear ends of the first and second shift levers or the third and fourth shift levers upon rotation of the associated select motor, each of the first and second shift actuators includes a shift motor and a ball screw for reciprocating the shift cylindrical body in the direction of the shift operation, and the ball screw is coupled to the associated shift motor and threadably mounted on the associated shift cylindrical body. 